Over the last twenty years, the study of carbohydrate-binding proteins (lectins) and their significance in immunology has intensified. Galectins, for example, embody a group of 15 β-galactoside-binding proteins that profoundly impact the differentiation of T lymphocytes (T cells) to help shape the strength of T cell-mediated inflammation, including autoimmune responses. In fact, galectin-1 can lower the level of effector T helper (Th) 1 and Th17 cell subsets, while promoting the survival of T regulatory (Treg) cell and generation of a Th2 cell profile. Controlling T cell differentiation in this manner yields an anti-inflammatory phenotype, thus effective galectin-1 molecules are useful as anti-inflammatory therapeutics.